Mikaela Kellner, a veteran of Swedish Ninja Warrior and police officer of 11 years, tackled an unsuspecting pickpocket to the ground in a Stockholm park. Photo / Instagram / @mikaelakellner

An off-duty Swedish police officer gave a pickpocket the shock of his life – when she tackled him to the ground wearing only a bikini.

Mikaela Kellner, a veteran of Swedish Ninja Warrior and police officer of 11 years, was sunbathing in a Stockholm park with friends when the unsuspecting pickpocket approached.

Under the guise of selling magazines for the homeless, the man began talking to the group of bikini-clad women.

It was only after he had left the group that one of her friends realised her mobile phone had vanished.

“I just acted on instinct and didn’t think about it so much until after we had pinned him down,” Kellner told The Local Sweden.

A snapshot of the arrest has gone viral after the athlete posted it to her Instagram account, where it has now received more than 6,000 likes in just one day.’When I sat there I looked over at our other two friends who are not police officers and realised that it probably looked pretty funny.’

But she confessed: ‘I would have stepped in no matter what my outfit. Had I been naked I would also have intervened.

“Nothing will stop me.”

As well as her work as a police officer, she is a fitness enthusiast and spends her free time power-lifting and doing Crossfit.

“He realised quite quickly that it wasn’t worth struggling.”

She said that she was just glad to draw attention to the tactics employed by pickpockets, warning that the theft was so subtle it was “like magic.”

Kellner said she began to suspect all was not as it seemed when the man would not take no for an answer when he approached them in the Ralambshov park in the Swedish capital.

Despite her warnings to her friends to keep an eye on their possessions, he was still able to make off with the phone after laying his pile of magazines over it and picking it up as he left.

“There was no time so I ran after him, maybe 15 metres or so,” she continued. “One of my friends is also a police officer, so we got hold of him.”

The pair of policewomen kept the thief pinned to the ground until some of their on-duty colleagues could arrive and arrest him.